Field of the Disclosure
The present disclosure relates generally to optical communication networks and, more particularly, to an optical receiver that includes multiple transimpedance amplifiers and a feedback control loop.
Description of the Related Art
Telecommunication, cable television and data communication systems use optical networks to rapidly convey large amounts of information between remote points. In an optical network, information is conveyed in the form of optical signals through optical fibers. Optical fibers may comprise thin strands of glass capable of communicating the signals over long distances. Optical networks often employ modulation schemes to convey information in the optical signals over the optical fibers. Such modulation schemes may include phase-shift keying (PSK), frequency-shift keying (FSK), amplitude-shift keying (ASK), pulse-amplitude modulation (PAM), and quadrature amplitude modulation (QAM).
Optical networks may also include various optical elements, such as amplifiers, dispersion compensators, multiplexer/demultiplexer filters, wavelength selective switches (WSS), optical switches, couplers, etc. to perform various operations within the network. In particular, optical networks may include optical-electrical-optical (O-E-O) regeneration at reconfigurable optical add-drop multiplexers (ROADMs) when the reach of an optical signal is limited in a single optical path.
As data rates for optical networks continue to increase, reaching up to 1 terabit/s (1 T) and beyond, the demands on optical signal-to-noise ratios (OSNR) also increase. High-speed optical receivers might include a photo detector that senses the incoming analog optical power and converts it into electrical current. In order to convert such a small current into a large voltage, some optical receivers include a circuit commonly referred to as a transimpedance amplifier (TIA).